Nonlinear Dynamic Characteristics of Marine Rotor-Bearing System under Heaving Motion

Table 1

The expression of nondimensional parameter.

Parameter description	Expression	Dimensional unit
Nondimensional frequency ratio η	η = ω/ω0	rad/s
Nondimensional time τ	τ = ωt	s
Nondimensional eccentricity α	α = e/c	m
Nondimensional displacement of rotor X	X = x/c	m
Nondimensional displacement of rotor Y	Y = y/c	m
Nondimensional displacement of ship	= x0/c	m
Nondimensional displacement of ship	= y0/c	m
Nondimensional Sommerfeld number σ		Pa·s
Nondimensional speed Ω0		rad/s
Nondimensional oil film force fi,i=x,y	fi = Fi/mg	N
Length-diameter ratio λ	λ = B/(2R)	m